Height control valve



June 28, 1960 R. E. SCHWARTZ 2,942,623

HEIGHT CONTROL VALVE Filed Nov. 7, 1957 3 Sheets-$heet 1 FIG] June 28, 1 R. E. SCHWARTZ HEIGHT CONTROL VALVE 3 Sheets-Sheet 2 Filed Nov. 7, 1957 FIG.5

Hill v Mme/W242: 02527 A 56/04 0272 2 Ivar/r475.

June 1950 R. E. SCHWARTZ 2,942,623

HEIGHT CONTROL VALVE Filed Nov. 7, 1957 3 sheets sheet 3 I37 gag Q 3:2 10

34 W wWm/m HEIGHT CONTROL VALVE Robert E. Schwartz, University City, Mo., assignor to Wagner-Electric Corporation, St. Louis, Mo., a corporation of Delaware rnea Nov. 7, 1951, so. No. 695,027 2 (Jlaims. (C1. 137-6215 This invention relates to pneumatic suspension systems and in particular to a height control valve employed therein. An objectof the present invention is to provide a height control valve having a neutral travel for regulating time delay incorporated in the valving which obviates any manual adjusting mechanism.

Another object of the present invention is to provide a height control valve having simplified, self-aligning gralving along with a simplified actuating means there- Still another object of the present invention is to provide a height control valve which obviates high pressure seals adjacent the hydraulic portion thereof.

. Still another object of the present invention is to provide a hei ht control valve which is economically manuatent factured lending itself readily to right or left hand use.

These and other objects and advantages will become apparent hereinafter.

Briefly, the present invention is embodied in a control valve mechanism including an oscillatable member carrying a yieldable torque connection in contact with a rotatable shaft and also having movement dampening means associated therewith whereby rotation of said shaft causes said yieldabl'e torque connection to apply a relatively constant force for a predetermined period of time to effect movement of said oscillatable member which is responsive to controllably actuate a cooperating unitary valve stem in order to provide communication between either inlet and working ports or working and exhaust ports.

The invention also consists in the parts and in the arrangement and combination of parts hereinafter described and claimed. In the accompanying drawings which form a part of this specification and wherein like numerals refer to like parts wherever they occur:

Fig. l is an elevational view of the referred embodiment of the present invention.

Fig. 2 is a sectional view taken along the line 2-2 of Fig. 1 showing the preferred embodiment in cross-secnon.

Fig. 3 is a sectional view taken along the line '3--3 of Fig. 1 showing the preferred embodiment in crosssection.

Fig. 4 is a partial sectional view taken along the line 4-4 of Fig. 3.

Fig. 5 is a partial sectional view taken along the line 5-'-5 of Fig. 2.

Fig. 6 is a sectional view taken along the line 6-6 of Fig. 7 showing the modification of the preferred embodiment in cross-section;

Fig. 7 is a sectional view taken along the line 77 of 'Fig. 6 showing the modification of the preferred embodiment in cross-section.

In reference to the drawings, it is well known in the automotive art that height control valves are employed to regulate the fluid pressure in air springs (not shown) which are interposed between two relatively movable H ice members (not shown), a sprung mass or vehicle frame,

and an unsprung mass or vehicle axle in order to mainably connected by suitable means, such as studs 5, having a gasket 6 interposed therebetwee'n; and the housing 4 is provided with an integrally formed mounting flange 7 for, attachment with the sprung mass, as above meritio'ned.

The lower housing 4 is provided with a chamber 8 which serves as a liquid reservoir and has valve stem receiving chambers or key type slots 9 integrally formed on each end thereof, and spring retaining recessm 10 are provided in the lower end of said key type slots. The central portion of the housing 4 is provided with a cross-bore 11 which intersects the chamber 4 and is axially aligned with a counterborelZ; and, the lower end of the chamber is connected with the mid-portion of a damping bore '13 by an opening 14. In order to adjust the degree of damping in the height control valve 1, as will be fully discussed hereinafter, an axially aligned bore 15 and c'ounterbore 16, Figs. 2 and 4, are horizontally spaced from the damping bore 13, and a passage 17 connects one end of said damping bore with the bore 15 while another passage 18 connects the other end of said damping bore with the counterbore 16 adjacent the shoulder formed by the juncture of the bore 15 and counterbore 16. In this manner, a seal carrying needle valve 19 which is threadedly received in the counterbore 16 is predeterminately positioned to restrict fluid flow through the passages 17 and 18.

Referring now to Figs. 2 and 3, the upper housing 3 of the leveling valve 1 is provided with spaced vertical chambers 20 and 21, respectively, adapted to open into and overlap the chamber 8 and one of the key slots 9 of the lower housing 4. The chamber 21 serves as a valve chamber and comprises a bore 22 axially interposed between a counterbore 23, which intersects the upper extremity of the housing 3, and a stepped counterbore 24 while a valve seat 25 is integrally formed between the bore 22 and 'counterbor'e 23. A horizontal passage 26 is interposed between the mid-portion of the counterbore 23 and an inlet port 27 which is adapted for connection with a fluid pressure source (not shown), and an exhaust port 28, having a filter assembly 29 positioned therein to prevent the entry of foreign particles, intersects the larger portion of the stepped counterbore 24 adjacent the shoulder formed therein. As shown in Fig. 5, the valve chamber bore 22 is connected by angular passages 30 to spaced working, oroutlet, ports 31 which are adapted for connection with a fluid pressure actuable device, such as the previously mentioned pneumatic spring (not shown).

Referring now to Figs. 1, 2, and 3', an end cap and seal assembly 32 is 'threadedlyreceived in and closes the upper endiof the c'ounterbore 23, and an inlet valve 33 is normally biased into scalable engagement with the cooperating valve seat 25 by a spring 34 interposed between said assembly and inlet valve. A valve stem 35, having a tubular exhaust passage 35 and crosspassage 37 in the upper portion thereof, extends coairially' through the valve chamber 21 and protrudes into the lower housing key slot 9 having spaced hubs 38 and 39 integrally formed on the lower portion thereof for neutral travel purposes (to be discussed hereinafter). A spring 49 is interposed between the lower valve stem hub 39 and the key slot recess it normally biasing the 1 upper end of the'stem 35 into scalable engagement with a the inlet valve 33 thereby closing the tubular exhaust passage 36 and cross-passage 37. A high pressure, sealing cup 41 is sealably interposed between the periphery .of the stem 35 and'the wall of the smaller portion of the stepped counterbore 24 and is seated by an upper valve guide member 42 positioned in abutment with the shoulder formed in said stepped counterbore; A diaphragm type s'eal,*or low pressure "seal; 43, carried by the stem 35 'near the mid-portion thereof, -is sealably interposed between said stem and the large portion of the stepped normally interrupting communication between said out- 1 i let ports and the 'exhaust port 28.

"The lower housing cross-bore 11 rotatably receives a shaft 45 having a flat 46 nearits mid-portion and another flat 47 on its inward end with a groove 48 adjacent thereto. A pin 49 is fixedly positioned in the cross-bore 11 and rotatably receives the. shaft groove 48 forming a ,bayonet' type lockingmeans retaining said shaft against displacement from said cross-bore. (The piny49 also serves as a thrust bearing absorbing any thrust forces applied-to said shaft by the actuating lever 2 which is i ,fixedly received by a reduced portion 50 on the outward end of 'saidshaft; and, a seal assembly, 51 positioned in the counterbore 12 seals thelshaft preventing the lo'ss of liquid from the chamber-8and obviating the entry of [foreign particles into the cross-bore 11.

An'oscillatable member or lever 52 is provided with a bore 53 and an integral tubular portion 54 which extends vertically into the upper housing chamber 20. ,The lever 52'is'also integrally provided with'a damping arm 55 V which extends vertically through the opening 14 into the damping bore 13 and a horizontally extending hub portion 56 to which one end of a valve stem actuating 57 is attached by suitable means, such as, the screw 58, while the fingers of the other end thereof are juxtadistance the actuating arm 57 must move before abutting either of the hubs 38' andr39 is the predetermined fneutral travel provided toobviate unwarranted movement of the stem35 and provide a time delayed operat-.

posed between the valve s'tem hubs'38 and 39. The -'1.

ing range for the control valve 1. The lever bore 53 I rotatably receives the'portion of the shaft 45 'on which 'the fiat 46 is formed, and a half bearing 59 is suitably interposed'therebetween having a depending flange 60 on one end thereof serving as a thrust bearing and journaling between; the. oscillatable lever .52 anda wall of the 1 lower housing chamber 9. p a t ,Tosecure the lever 52 to the shaft '45, so that under certain conditions the lever 52 will oscillate with'the shaft and under other conditions the shaft 45 may 050111 laterelatively to the-lever, there isiprovided a yieldable torque connection 61 .This torque eonnection 61 com prises a plungerf62 slidableinthe tubular -portion'54 of the-'oscillatable lever 5 2 and normally'urged into yieldable engagementwith the flat 46 on the shaft 45 by the predetermined compressive force of a spring assembly63 retained in said tubular portionagainst displacement by a snap ring 64 carried in the upper end of said tubular portion. In this manner, the yieldable torque connection 61 exerts a relatively constant force to move the lever 52 Withth eshaft'45." it 1 V a In order to actuate the height control valve '1 only in I SPQ t a ede .ne ys o a ve .tn vement through the restricted passages v17 -and 18 affording the so 1316,)18 at a predetermined distance from the unsprung 4 between theaforementioned sprung and unsprung masses and obviate actuation due to the more rapid and of less amplitude movements of said masses caused by road conditions, the height control valve 1 is provided with a damping mechanism 65 which, combined with the yieldable connection 61 between the shaft 45 and lever 52, affords a time delay permitting said leveling valve to be actuated at slow relative movementsof the sprung and V unsprung masses and obviates actuation at the faster movements thereof. This damping mechanism 65 comprises a piston 66 slidable in the damping bore 13 and provided with a vertical slot 67 therethrough in which the lower end of the oscjllatable lever damping arm 55 is received. The endsofthe damping gbo re 13. are closed by 'a welch plug 68 pressed-into a'recess 69 at one end and a seal carrying closure member 40 positioned in a recess 71 in the other end by a snap ring 72 In this manner displacement chambers '73 and -74 -are formed between'the opposed endsof the damping piston 66 and the welch plug 68 and closure member 70, respectively. .Asdescribed above, the oscillatable lever 52 is mechanicallYconnected to the reciprocati-ve damping piston 66 of the damping mechanism 65whereby tilting movement of said lever is transmitted I to the damping piston 66 causing it to displace fluid from one displacement chamber 'to the other via thev predeterminately restricted passages and18.. a V 1 Operation Assuming'that the sprung mass, or] frame of the vehimass, or axle, of the vehicle, the s prung mass is moved -downwardlyfwhen the vehicle load is increased thereby -moving the'control arm 2 'in arcounterclockwise direction; In this manner the shaft 45 is also rotated in a icounterclockwise direction; and; since the yieldable' connection 61 exerts a relatively constantzforce to rotate or .move: the tiltable member 52with the shaft 45, a rela- -tively constant force is also imparted to the damping arm 5L5 to move. the piston 66 rightwardinthe damping bore 13. This movement displaces fluidfrom' the displacement chamber'73'throu'gh the restricted passages 17 and '18 into-the ldisplacement chamber 74 affording a predetermined time delay before'the valve actuating arm 57 is movedrthrough its neutral travel into abutment with the upper hub, 38Ion thevalve stem 35. Further movement 'ofi'the' actuating-armx57 moves the valve stem 35 'upwardly to open the inlet'valve 33 against the compressivet force of the spring 34 thereby affording pressure fluid communication between the inlet-27 and working ports 31' to inflate the pneumatic springs (not shown). As these pneumatic springs areinflated, the sprung mass is raised to the aforementioned predetermined distance above the unsprungmass which results in a consequent, clockwise rotation of the :control arm} and shaft 45.

In this manner, the leverf52 and'parts associated'therewith are returned to their original positions, and the compressiveforce of the spring 34 reseats the inlet valve 33'and returns the valve stem 35 to its original pOSitiOn;T c a ,In theevent the vehicle load is lessened, the sprung mass is moved upwardly resulting in an increased distance'between the sprung and ,unsprung masses greater than the predetermined distance; consequently, the control arm; and shaft 45yarerotated in a'clockwise'direction, and the relatively constant force applied" by the 'yieldable torque connection 61;;causes the tiltable lever 52 to move or rotatezwithsaidishaftfi, Asa result, a relatively constant force is also imparted to thefdamping :arm 55 :movingthe piston 66 leftwardly in the damping bore 13, and this movementdisplaces pressure fluid-from the displacement chamber 74; into the chamber 1 73 necessary time delay before the valve actuating arm 57 1s moved through its neutral travel into abutment with the ow nub ,wi a hera i s ew -,1 .fi the 239K? meat of the actuating arm 57 moves the valve stem downwardly against the compressive force of the spring 40. In this manner the upper end of the valve stem is disengaged from the inlet valve 33 thereby affording pressure fluid communication between the working ports 31 and exhaust port 28 via the valve chamber bore 22 and the tubular exhaust passage 36 and cross-passage 37 in the upper portion of the valve stem 35. .As the pneumatic springs are deflated, the spring mass is lowered to the aforementioned predetermined distance above the unsprung mass which results in a consequent counterclock- ,wise rotation of the control arm 2 and shaft 45. In this manner, the lever 52 and parts associated therewith are returned to their original positions, and the compressive force of the spring 40 returns the valve stem 35 to-its original position sealably re-engaging the upper end thereof with the inlet valve 33 to close the valve stem exhaust passage 36 and again interrupt communication between the working ports 31 and the exhaust port 28,

As described above, slow relative movement between the sprung and unsprung masses causes a force to be ap plied to the damping piston 66 for a sufficient time to effect operation of the valve stem 35; however, insufficient time is allowed for valve stem operation due to more rapid and of less amplitude movements between said masses caused by road conditions. Since the damping piston 66 moves at a predetermined rate due to the desired degree of damping obtainable, the rotational rate or angular velocity of the lever 52 is also limited to this predetermined rate; therefore, if the torque input of the rapidly moving control arm 2 and shaft tends to rotate the lever 52 at a rate greater than the above.- mentioned predetermined rate, the torque connection 61 yields, and the plunger 62 is moved upwardly by the shaft 45 against the compressive force of the spring assembly 63. In this manner, the yieidable torque connection 61 obviates movement of the lever 52 due to rapid movements of the control arm 2, and said lever and damping mechanism 65 remain substantially stationary under these conditions.

It is apparent that a predetermined load increase or decrease on the sprung mass is permitted due to the neutral travel of the valve stem actuating arm 57 which provides an operating range and obviates immediate actuation of the control valve 1. This neutral trave is the angle through which the actuating arm 57 must move before it abuts against either of the valve stem hubs 38 and 39. As a result, quick loading and unloading of the vehicle will not cause actuation of the height control valve 1, and this delayed neutral trave also obviates actuation of said height control valve if slight movements are imparted to the lever 52 during the abovementioned high rate movements of the control arm 2.

In addition to having the predetermined neutral travel machined into the valve stem 35, it is also apparent that "the valvi'ng controlling the inlet, working, and exhaust ports precludes the need for minute manual valve adjustments to establish this rather precise neutral trave distance. The valve stem 35 and parts associated therewith in the valve chamber 21 are self-aligning with reference only to said valve chamber which is most conducive to maintenance and repair. Further, the valve stem 35 is automatically positioned vertically in the valve chamber 21 by the opposing compressive forces of springs 34 and 40.

It is also apparent that the valve and porting combination in the chamber 21 obviates high pressure seals between the pneumatic and hydraulic portions thereof, that is the exhaust port 28 which is at atmospheric pressures is interposed between the high pressure inlet and working ports 27 and 31 and the hydraulic portion, or chambers '8' and 20, of the valve 1. As a result, the possibility of high pressure air entering the chambers 8 and 20 is precluded, and the diaphragm type seal 43 can be utilized between the exhaust portion of the chamber 21 and the chamber '8. In view of the above, precluding the any of high pressure air into the chamber 8 not only preserves the integrity of the damping mechanism 65 but also enhances the life of the bearing 59., the bearing seal 51, and the fluid reserve. I V

Among the obvious advantages of the present invention are the ease of assembly and the simplicity of inanufacture The height control valve '1 is alsoprovided with the feature of adaptability to left or right hand use. By merely rotating the upper housing 3 one hundred and eighty degrees (180) and reversing the position of the control arm 2, the height control valve 1 is converted from left hand use, shown; to right hand use.

Referrin to Fi s. '6 and 7, the modification of the preferredembodiment comprises a height control valve 1121 having a housing 102 to which a cover late 103 is attached by suitable means, such as studs 10 1, with a gasket 105 sealably interposed therebetween; and, a plurali'ty of through bolt holes 106 are provided in said housing for mounting purposes.

The housing 102 is pfovided with a damping bore 107 and a valve chamber 108, whichis horizontally spaced therefrom, each having one of their ends intersecting an upper chamber or liquid reservoir 109 while the other ends thereof interset the lower extremity of said housing. A cross bore 109a is also provided through the housing 102 intersecting the upper chamber 109 near the mid-portion thereof. V

The valve chamber 103 comprises a bore 110 axially interposed between upper and lower eou tefbor es 111 and 112, respectively, and an' integrally formed valve seat 113 is provided between the tapered portion of the bore 110 and the lower couhte'rborelfl. An inlet pert 114 is adapted for connection with the pressure source intersects the lower counterbore 112 near the mid-porlieu thereof while an outlet or working port 115 adapted for connection with the pneumatic springs intersects the tapered portion of the bore 110, and an exhaust port 116 intersects the upper coiinterbore 111 adjacent its juncture with the bore 110. p

An end cap and seal assembly 117 is th'readedly received in and closes the lower end of the counterbore 112, and an inlet valve 118 is normally biased into 'sealable engagement with the cooperating valve seat 113 by a spring 119 interposed between said assembly and inlet valve. A valve stem 120,, having a tubular exhaust passage 121 and cross-passage 122 in the lower portion thereof, extends axially through the valve chamber 108 and protrudes into fhe 11.13.1381 chamber 106 with spaced hubs 1'23 and 124 integrally formed on the pper portion thereof for neutral travel purposes. Aspring 125 is interposed between the upper valvesstem hub 123 and the cover plate 103 normally biasing the lower end of the stem 35 into scalable engagement with the inlet valve 118 thereby closing the exhaust passage'121 and cross-passage 122. A sealing cup 126 is s'ea'lably interposed between the periphery of the stem '120 and the wall of the valve chamber boref 110 and is seated by a lower valve guide member 127 positioned in, abutment with the shoulder formed at the juncture of said bore and the counterbore 111. Another seal 128 is sealably interposed between the stem .120 and the wall of the counterbore 111 and is ,abuttin'gly interposed between the lower valve guide 127 and an upper valve guide member 129 which is retained againstdisplacement from the counterbore 111 by a snap ring 130 carried adjacent the upper end thereof.- As described above, the inlet valve 118 normally interrupts communication between the inlet port 114 and outletport 115, and the scalable engagement between said inlet valve and the "lower end of the stem .120 normally interrupts communication be tween the outlet port 115 and exhaust port 116.

An end of the housing cross bore 109a is closed by a welch plug 131 and a shaft 132 is rotatably received outer end havingra reduced portion 136 thereon on which is fixedly received acontrol arm'137.

An oscillatable memberor 'lever"138 is provided 'a tubular portion 139 onefen'd, of whichis intersected 'by aj'cross ibore 140, which rotatably receives the portions of t he' shaft 132 having the flat 134 thereon,jand

ahalf bearing, 41 is interposed between saidshaft'and bearingf141' also, having, depending side'edg'es'142 which serve as thrusfbcarings journalled between said lever and the side walls of the upperchamber 109 adjacent the with said'shaft 'and under other conditions said shaft 1 i.

will oscillate relatively to said lever, there 'is'provided a yieldable torque connection 143. This torque con:

7 8'" r tages sought therefor. It is to be understood, however, that'the foregoing description-and the "accompanying drawings have'been presented only by way of illustra- 7 cross bore on the load carryingi side of said shaftpsaidi tion-and example and that changes, alterations, and modi fications of the-present disclosure which will be readily apparent to one skilled in the art are contemplated as ,being within the scope of the present invention which limited only by the claims whichfollow; i 7

, What is claimed is as'follows: V, 1. In a height control valve-including a housing having inlet,- outlet and exhaust ports and a normally closed valveicontr'olling communication between said inlet and outlet'ports, aunitary valve'stem adapted to actuate said valve, an exhaust passage through one end of said valve stemcontr'olling-communication betweenfls'aid outlet and exhaust ports,'spaced projections adjac'ent to'the other nection' 143jcomprises 'a piston 144 slidable in the tu-jf ,ofjform s an integral damping i arm 149 having a slot ISOther'ein; ,Thecontrol arm 147 extends horizontally 'from the oscillatable member 138 whereby the valve stem120 is receivedin the slot 148 so that said control arm is juxtaposed with'and adapted for abutrnent' with the spaced valve stem hubs 123 and 124. Thedarnp; ing a'rrn 149 extends horizontally along the lower portion of the oscillatable member 133 and is adapted to control a damping mechanism 151. 'The damping mechanism '151 comprises a piston 152 slidably receivedin the bore 107 and having a vertical'bore 153therethrough with a seat 154'formed at the lowerjend' of said'vertical here, said piston also having a restrictedv passage 155 between its faces. 8 A knuckle'joint 6 is always biased end'portion of said unitary valve stem, springmeans' in abutment with one of the projections urging said valve stem into scalable engagementwith the valve to close said exhaust'passage, a shaft rotatably mountedin' said housing, a lever'carr-ied on said shaftand movable therewith, predeterminately yieldable means normally effecting concert movement between said shaft and lever, movement damping means connected with said lever and etfective to cause said yieldable means to yield at predetermined angular velocities of said shaft, a control arm carried by saidrlever and normally juxtaposed between the projections whereby movement of said lever "moves the control arm into contact with one'or the other of the projections to'move said valve stem in a valve opening direction and open communication between said inlet and outlet ports or in an exhaust passageopening directionand open communication betweensaid outlet and into sealable engagement with the cooperating seat 154 7 knuckle joint'having an integral stem i158 extending coaxially through the vertical bore 153 with the upper end thereof retained in the control arm slot 150. There fore, the knuckle joint 156 is merely a connecting link between the Qarm 149 and the piston 15?. providing a simplified means of assembly. 7 V v The modified height control valve 101 functions exactly 6 as the prefcrred embodiment with the 'exceptionof the exhaust ports. r a a i '2; In a height control valve including a housing-having inlet, outlet, and exhaust ports, valve means for controlling communication between said inlet and outlet ports, a valvestem having an exhaust passage therein for controlling communication between said outlet and exhaust ports, spaced projections adjacent to theother end "of said unitary'valve stem, said valve stem being nortension, movement damping means in contacting relation damping mechanism 151:which has thejsame effectj'albeit' of different construction. When'the lever 138 tilts" in meditation the damping arm;149 compresses the spring 4 157 vforcing the'damping piston 1 52 downward in the bore 107 and allowingfluidflowthrough-the restricted passage 155 to effect dam-ping. When the lever 133 tilts in the other direction the'damping arm 149'pulls the knuckle joint 156 further into scalable engagement with the seat 154 forcing the' damping piston "152 upward in the bore 1 0T'whic h allows fluidflow through the re strictedfpiiss'agejI SS toeifect damping. I Thus; it isapparent that there has been provided-a novel'height control 'valve for a vehicle, pneumatic sus pension system which fulfills all the objects and advan-' with said damping arm on said lever, said plunger and said'damping means allowing relative movement between said shaft and said lever upon a predetermined rotating velocity of said shaft, anda single connection between saidlever and said spaced projections on said valve stem whereby movement of said lever in one direction opens communication between said inlet and outlet and in the other direction opens communication between said outlet and exhaust ports. 4

References Cited in'the fileofj this patent UNITED STATES PATENTS 1931 1,834,634 r Nash D n; 2,171,316 Van Sittent 'Aug.'29, 1939 2,588,798 7 Bone w Man 11, 1952 2,670,201 Rossman Y V Feb.' 23, 1954 2,733,931 Reid Feb. 7, 1956 V FOREIGN'PATENTS Great Britain of 1957 

